Over the years many attempts have been made to modify or enhance the color of one's eyes using colored contact lenses with varying degrees of success. Attempts to produce an opaque lens with a natural appearance are disclosed in U.S. Pat. No. 3,536,386, (Spivak); U.S. Pat. No. 3,679,504 (Wichterle); U.S. Pat. No. 3,712,718 (LeGrand), U.S. Pat. No. 4,460,523 (Neefe), U.S. Pat. No. 4,719,657 (Bawa), U.S. Pat. No. 4,744,647 (Meshel et al.), U.S. Pat. No. 4,634,449 (Jenkins); European Patent Publication No. 0 309 154 (Allergan) and U.K. Patent Application No. 2 202 540 A (IGEL).
Commercial success was achieved by the colored contact lens described in Knapp (in U.S. Pat. No. 4,582,402) which discloses a contact lens having, in its preferred embodiment, colored, opaque dots. The Knapp lens provides a natural appearance with a lens that is simple and inexpensive to produce, using a simple one-color printed dot pattern. Although, in Knapp, the intermittent pattern of dots does not fully cover the iris, the invention provides a sufficient density of dots that a masking effect gives the appearance of a continuous color when viewed by an ordinary observer. Knapp also discloses that the printing step may be repeated one or more-times using different patterns in different colors, since upon close examination the iris's of many persons are found to contain more than one color. The printed pattern need not be absolutely uniform, allowing for enhancement of the fine structure of the iris. The one-color Knapp lenses currently achieving commercial success have their dots arranged in an irregular pattern to enhance the structure of the iris. However, neither the Knapp commercial lenses, nor the Knapp patent disclose or suggest a contact lens designed for the person having dark-colored eyes in which the colored contact lens provides a subtle change or enhancement to the eyes of a dark-eyed person.
Various efforts have been made to improve on the Knapp lens. U.S. Pat. No. 5,414,477 to Jahnke discloses the application of the intermittent ink pattern in two or more portions of distinct shades of colorant to provide a more natural appearance.
Other attempts to create a more natural appearing lens include U.S. Pat. No. 5,120,121 to Rawlings which discloses a cluster of interconnecting lines radiating from the periphery of the pupil portion to the periphery of the iris portion. Further, European Patent No. 0 472 496 A2 shows a contact lens having a pattern of lines that attempts to replicate the lines found in the iris.
Although many attempts have been made to create colored contact lenses that change or modify the color of the iris, none of the colored contact lenses have addressed the particular subtle change or enhancement required by a person having dark-eyes who wants a subtle enhancement rather than a dramatic change in eye color.